I had been familiar with the concept of vincible and invincible ignorance, but I had not been familiar with the more full taxonomy of ignorance. I especially liked these variants, especially in the context of the quote:

Ignorance stemming from making little or no effort is termed crass or supine; it removes little or no guilt. Deliberately fostered ignorance is affected or studied; it can increase guilt.

I’ve always liked this quote and I happened upon it last night again. Regardless of Spencer’s (somewhat unearned) academic infamy as the father of Social Darwinism, it was other aspects of his thought that penetrated the way we think today.

In particular, Spencer emphasized the ability of individuals to learn and discern. His attempt to integrate 19th century concepts of evolution into this idea of perfectibility — an attempt to merge “nature” and “nurture” — ended up obscuring that optimistic message behind the more arbitrary and harsh ideas of natural selection.

His suggestion here, that everyone could use the ideals of scientific enquiry to progress and improve, highlights the most attractive dimension of his thinking.